# Leonardo Alert Service Bulletin 109EP-168: No revision named - Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2021-0606, the docket of AD 2021-24-11. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Leonardo Alert Service Bulletin 109EP-168](https://openairdocs.org/service-documents/leonardo/109ep-168.md) - Title as filed: Leonardo Helicopters ASB No_109EP-168 - Pages: 20 - PDF: https://openairdocs.org/files/sha256/85/df/85dffd166da75b7a091b54e86de50b348698401d607135e4bd3315ea48c4cdab - Page: https://openairdocs.org/service-documents/leonardo/109ep-168/file/85dffd166da7 ## Text Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 N° 109EP-168 DA TE: June 28, 2019 REV. : / - March 15, 2017 Pa ge 1 of 19 TITLE ATA 32 – INSPECTION OF LH/RH ENHANCED MAIN LANDING GEAR STRUT ASSY P /N 109-0503-45 REVISION LOG New Issue. An appropriate entry should be made in the aircraft log book upon accomplishment. If ownership of aircraft has changed, please, forward to new owner. Leonardo S.p.A. Via Giovanni Agusta, 520 21017 Cascina Costa di Samarate (VA) Italy Tel.: +39 0331 229111 - Fax: +39 0331 229605/222595 ALERT SERVICE BULLETIN ### Page 2 S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 2 of 19 REVISION: / 1. PLANNING INFORMATION A. EFFECTIVITY NOTE Refer to Figure 1 for LH/RH Wheel Axle P/N and S/N identification. All the Leonardo S.p.A. A109E helicopters equipped w ith LH/RH Enhanced Main Landing Gear Strut. Assy P/N 109-0503-45-101/-102 which install the LH/RH Wheel Axle with P/N listed in Table 1 and S/N listed in Table 2. LH/RH Enhanced MLG Strut. Assy P/N LH/RH Wheel Axle P/N 109-0503-45-101 M019-01H003-101 109-0503-45-102 M019-01H003-102 Table 1 LH Wheel Axle P/N M019-01H003-101 RH Wheel Axle P/N M019-01H003-102 from S/N 1 to S/N 146 from S/N 1 to S/N 147 from S/N 152 to S/N 172 from S/N 153 to S/N 173 Table 2 NOTE If a LH/RH Wheel Axle with P/N listed in Table 1 and S/N listed in Table 2 is installed on a MLG strut. assy in stock, attach a copy of this Service Bulletin to its box for future compliance before the MLG strut. assy installation on the helicopter. B. COMPLIANCE Within and not later than 50 flight hours or 200 landings or 6 months, whichever occurs first, after the issue of this Service Bulletin and subsequently every 12 months. C. CONCURRENT REQUIREMENTS N.A. D. REASON This Service Bulletin is issued in order to introduce a periodical inspection of the LH/RH Enhanced Main Landing Gear Strut. Assy P/N 109-0503-45-101/-102. ### Page 3 S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 3 of 19 E. DESCRIPTION On two A109E helicopter in service, a failure of the RH Main Landing Gear Wheel Assy was reported. Further investigation revealed that the cause of the failure was caused by stress corrosion cracking, enhanced by local presence of hydrogen embrittlement, on the threaded end of the RH Enhanced Main Landing Gear Strut. Assy P/N 109-0503-45-102, where lack of cadmium plating was observed. This Service Bulletin is issued with the purpose to provide the necessary instruction to perform a periodical liquid penetrant inspection to verify the presence of cracks on the threaded end of the LH and RH Enhanced Main Landing Gear Strut. Assy P/N 109-0503-45-101/-102 and to apply a corrosion protective compound at wheel re-installation. An alternative inspection method with magnetic particles is provided, too. F. APPROVAL The technical content of this Service Bulletin is approved under the authority of DOA nr. EASA.21.J.005. For helicopters registered under other Aviation Authorities, before applying the Service Bulletin, applicable Aviation Authority approval must be checked within Leonardo Helicopters customer portal. EASA states mandatory compliance with inspections, modifications or technical directives and related time of compliance by means of relevant Airworthiness Directives. If an aircraft listed in the effectivity embodies a modification or repair not LHD certified and affecting the content of this Service Bulletin, it is responsibility of the Owner/Operator to obtain a formal approval by Aviation Authority having jurisdiction on the aircraft, for any adaptation necessary before incorporation of the present Service Bulletin. G. MANPOWER To comply with this Service Bulletin 2 (two) MMH are deemed necessary. MMH are based on hands-on time and can change with personnel and facilities available. H. WEIGHT AND BALANCE N.A. ### Page 4 S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 4 of 19 REVISION: / I. REFERENCES 1) PUBLICATIONS SECTION/PARAGRAPH DESCRIPTION PART DM01 00-20-1 Helicopter safety - DM02 07-10-2 Jacking and lowering of helicopter - DM03 32-41-14 Main wheels - Removal/installation - DM04 32-11-10 Left/right main landing gear struts - Removal/installation - DM05 CMM 32-11-19 4 th issue Main Landing Gear - Component Maintenance Manual (only for authorized service station) - 2) ACRONYMS AR As Required CMM Component Maintenance Manual DM Data Module DOA Design Organization Approval EASA European Aviation Safety Agency IPC Illustrated Part Catalog LH Left LHD Leonardo Helicopters MLG Main Landing Gear MM Maintenance Manual MMH Maintenance Man Hours N.A. Not Applicable RH Right P/N Part Number SB Service Bulletin S/N Serial Number 3) ANNEX Annex A A109E MLG Liquid Penetrant Inspection. Annex B A109E MLG Magnetic Particle Inspection J. PUBLICATIONS AFFECTED A109E-MPM Maintenance Planning Manual ### Page 5 S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 5 of 19 K. SOFTWARE ACCOMPLISHMENT SUMMARY N.A. ### Page 6 S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 6 of 19 REVISION: / 2. MATERIAL INFORMATION A. REQUIRED MATERIALS 1) PARTS # P/N ALTERNATIVE P/N DESCRIPTION Q.TY LVL NOTE LOG P/N 1 MS24665-374 MS24665-372 Cotter pin 2 . - Refer also to IPC for the spares materials required to comply with the MM Paragraphs referenced in the accomplishment instructions. 2) CONSUMABLES The following consumable materials, or equivalent, are necessary to accomplish this Service Bulletin: # Spec./LHD code number DESCRIPTION Q.TY NOTE PART 2 MIL-PRF-16173, Cl I & II, Grade 1 (LHD cod. 999999999000000191) Tectyl 891D (C509) AR (1) - 3 MIL-PRF-16173, Cl I, Grade 4 (LHD cod. 999999999000000190) Tectyl 846 (C532) AR (1) - 4 SAE-AMS-2644 TY I, Method C, Level 3 Dye Penetrant AR (1)(2) - 5 SAE-AMS-2644, Form D Developer AR (1)(2) - 6 SAE-AMS-2644 Cl II Solvent (C290) AR (1)(2) - 7 ASTM F945 Ardrox 6333 (C292) AR (1) - 8 Commercial Alkaline Steel Cleaner AR (1) - Refer also to AMDI for the consumable materials required to comply with the MM Paragraphs referenced in the accomplishment instructions. 3) LOGISTIC MATRIX N.A. NOTE (1) Local supply. (2) This material shall be certified in accordance with AMS2644, obtained from a supplier listed in QPL-AMS2644 and supplied in aerosol cans packaging. B. SPECIAL TOOLS Refer also to PTUM for the special tools required to comply with the MM Paragraphs referenced in the accomplishment instructions. C. INDUSTRY SUPPORT INFORMATION Owners/Operators who comply with the instructions of this Service Bulletin no later than the applicable date in the “Compliance” section will be eligible to receive ### Page 7 S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 7 of 19 REQUIRED MATERIALS on free of charge basis, except for Consumable Materials and Special Tools. NOTE: Customers who fail to comply with the instructions in this Service Bulletin before the compliance date are not eligible for the aforementioned special policy. Please Issue relevant MMIR form to your Warranty Administration Dpt. Accompanied by INSPECTION REPORT and PICTURE of the affected area. NOTE: The INSPECTION REPORT and PICTURE are mandatory; in case the MMIR is not accompanied by these documents, it will be rejected. NOTE: WRM will include RETURN MATERIAL AUTHORIZATION (RMA) number; the unit removed from the aircraft has to be returned to LHD as per instructions defined into LHD Information Letter GEN-15-047. ### Page 8 S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 8 of 19 REVISION: / 3. ACCOMPLISHMENT INSTRUCTIONS GENERAL NOTES a) Place an identification tag on all components that are re-usable, including the attaching hardware that has been removed to gain access to the modification area and adequately protect them until their later re-use. b) Exposed thread surface and nut must be protected using a layer of tectyl according to MIL-C-16173 grade I. 1. In accordance with the instructions given in MM P aragraph 00-20-1, prepare the helicopter on ground for a safe maintenance. Disconnect the battery, all electrical power sources and/or the external power supply. 2. In accordance with the instructions given in MM Paragraph 07-10-2, lift the helicopter on jacks. 3. In accordance with the instructions given in MM Paragraph 32-41-14 remove the LH and RH MLG wheel assy. NOTE Magnetic Inspection in Annex B is a valid alternative to the liquid penetrant inspection. The two methods are equivalent. 4. In accordance with the instruction given in the A nnex A, perform the liquid penetrant inspection on the threaded end of the LH and RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. Cracks are not allowed. 5. In case of no findings, proceed to step 7. NOTE In case of finding contact Product Support Engineering (aw109.mbx.aw@leonardocompany.com). 6. In case of findings, perform the replacement of t he damaged leg as described in the following procedure: NOTE The following steps are applicable both on LH and RH MLG strut. assy. 6.1 In accordance with the instructions given in MM Paragraph 32-11-10, remove ### Page 9 S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 9 of 19 and return to LHD the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. 6.2 In accordance with the instructions given in MM Paragraph 32-11-10, install the new LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. 7. In accordance with the instructions given in MM Paragraph 32-41-14 reinstall the LH and RH MLG wheel assy. 8. Apply corrosion preventive compound MIL-PRF-16173 Grade 1 (Tectyl 891D) or Grade 4 (Tectyl 846) on the exposed surface of the threaded end and on inner surface of the end lightening hole of the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. 9. Record for compliance with this Service Bulletin on the component log card. 10. Return the helicopter to a ready to flight condition and record for compliance with this Service Bulletin on the helicopter logbook. 11. Send the attached compliance form to the following mail box: aw109.mbx.aw@leonardocompany.com As an alternative, gain access to My Communications section on Leonardo WebPortal and compile the “Service Bulletin Application Communication”.  Non cancellare mai questo segnalibro Non cancellare mai interruzione sezione  ### Page 10 S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 10 of 19 REVISION: / (FOR REFERENCE ONLY) ### Page 11 ANNEX A S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 11 of 19 ANNEX A A109E MAIN LANDING GEAR LIQUID PENETRANT INSPECTION ### Page 12 ANNEX A S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 12 of 19 REVISION: / 1 PURPOSE AND APPLICABILITY This procedure details the requirements for the Liquid Penetrant Inspection (PT) on the following P/Ns: MAG P/N DESCRIPTION M019-01H003-101 Wheel Axle LH M019-01H003-102 Wheel Axle RH Purpose of this inspection is the detection of any possible crack starting from the root of the bottom of the thread of the hub; the inspection of this procedure shall be performed on all the thread of the hub after the removal of the wheel. 2 REFERENCES The following documents in their last revision are considered part of this procedure: ASTM E1417 Standard Practice for Liquid Penetrant Testing; ASTM E3022 Standard Practice for Measurement of Emission Characteristics and Requirements for LED UV-A Lamps Used in Fluorescent Penetrant and Magnetic Particle Testing; EN4179/NAS410 Qualification and approval of personnel for non-destructive testing; QPL AMS2644 Qualified Product List of Inspection Materials, Penetrant; SAE AMS2644 Inspection Materials, Penetrant. 3 EQUIPMENT AND MATERIALS The following materials, equipment and tools are requested. 3.1 MATERIALS a. Dye Penetrant SAE-AMS-2644 TY I, Method C, Level 3; b. Developer SAE-AMS-2644 Form D; c. Solvent SAE-AMS-2644 Class 2. All the above materials shall be certified in accordance with AMS2644, obtained from a supplier listed in QPL-AMS2644 and supplied in aerosol cans packaging. 3.2 EQUIPMENT/TOOLS a. A booth suitable for darkening the area of inspection up to an illuminance of 20 lux maximum; b. a Luxmeter for checking the illuminance (20 lux maximum on the part during the inspection and the 1,000 lux minimum for the assessment of indications); ### Page 13 ANNEX A S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 13 of 19 c. a Radiometer for checking the minimum 1,200 µW/cm2 on the part during the inspection; d. a UV-A lamp suitable for achieving an irradiance of at least 1,200 µW/cm2 on the area of inspection at 38 cm from the lamp; in case of use of a LED UV-A lamp, it shall be certified in accordance with ASTM E3022; e. a white light lamp suitable for achieving an illuminance of at least 1,000 lux on the inspection surface; f. a clean and dry soft plastic brush (an unused toothbrush could be suitable for the purpose); g. some small clean and dry soft bristled brush; h. a circular inspection mirror of about 80 mm diameter; i. some clean, dry and free lint cloth or paper; j. a magnification lens (max 5X); k. an environmental thermometer. 4 PERSONNEL Personnel performing the inspection of this procedure and appointed for the interpretation and evaluation of the indications shall be qualified as a minimum Level 2 in the PT Method and for the Technique “Portable System Type 1, Method C” in accordance with the requirements of EN4179/NAS410. The personnel shall also be familiar with the purpose of this procedure. 5 PART PREPARATION Due to the irregularity of the inspection surface for the presence of the thread, the preparation shall be done in a very careful way. It shall be carried out by means of the soft plastic brush (toothbrush) and the Class 2 solvent; the operation shall be repeated as many times as necessary in order to remove any surface contamination. Any abrasion tool is forbidden. The accuracy of the cleaning on the entire inspection surface shall be verified under white light at 1,000 lux minimum and with the use of the mirror and the lens as necessary. 6 INSPECTION If not otherwise specified below, the inspection process shall be in compliance with the requirements of ASTM E1417. ### Page 14 ANNEX A S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 14 of 19 REVISION: / 6.1 TEMPERATURE CONTROL The inspection can only be carried out when the temperature of the room, part, and materials is in the range of 10-45°C (50-113 °F). 6.2 PENETRANT APPLICATION The penetrant shall be applied on all the threaded part of the hub by means of the soft bristled brush and verified under black light and with the mirror as necessary for the complete coverage of the thread. The penetrant dwell time shall be 30 minutes minimum and shall not exceed 1 hour. 6.3 PENETRANT REMOVAL The heavy excess of the penetrant shall be removed using dry clothes or paper; the final removal shall be then completed using cloths or paper dampened with the Class 2 solvent; the use of cloths or paper soaked with the solvent or the spraying of solvent directly on to the part is prohibited. The complete removal of the excess of penetrant shall be verified under black light at 1,200 µW/cm2 minimum of and with the use of the mirror and the lens as necessary. 6.4 DEVELOPER APPLICATION The developer shall be applied to the part when the solvent is completely evaporated; the application shall be done directly from the aerosol can, which requires agitating regularly to keep the developer suspended in the carrier vehicle. The correct application shall result in a thin and uniform film and the color of the part should be just visible through the developer. The developer dwell time shall be 10 minutes minimum and shall not exceed 1 hour. 6.5 OBSERVATION REQUIREMENTS The part shall be covered with the darkening booth with the black light lamp turned on inside; the following conditions shall be verified on the inspection surface: a) an irradiance of at least 1,200 µW/cm2, b) an illuminance maximum of 20 lux. During the observation of the part, the operator shall not wear photochromic or dark glasses and shall ensure there are no sources of fluorescence in the ### Page 15 ANNEX A S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 15 of 19 inspection area (e.g. white paper and/or cloths). The operator shall stay in the booth a minimum of one minute for dark adaptation before carrying out the inspection. The part shall be observed very carefully on its entire surface with the use of a mirror as necessary. Any fluorescent indication shall be identified for interpretation and evaluation. 6.6 INTERPRETATION AND EVALUATION Parts resulting not affected by any indication will remain in service. Vice versa any indication of fluorescence shall be interpreted by lightly wiping with a cloth or paper or a small soft bristled brush, dampened with the Class 2 solvent. This shall be done for a maximum of 3 wipes; then the developer application on the area affected by the suspected discontinuity shall be done under the same conditions of paragraph 6.4. Any indication confirmed by the wipe-off will be evaluated under 1,000 lux minimum of white light and the lens for confirmation of crack that will result in the removal of the part from service. Any indication confirmed by the wipe-off, evaluated under white light as before, but assessed to be due to some burr, shall be reported for further evaluation. Any indication not confirmed by the wipe-off shall be considered false and the part will remain in service. 6.7 POST INSPECTION CLEANING Parts evaluated for remaining in service shall be cleaned from any inspection residues by means of the soft plastic brush and the Class 2 solvent and the operation shall be repeated as many times as necessary in order to remove any surface contamination. In this case, the solvent should be sprayed directly onto the part and into the central hole of the hub for complete fluorescence removal to be verified under black light. ### Page 16 ANNEX B S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 16 of 19 REVISION: / ANNEX B A109E MAIN LANDING GEAR MAGNETIC PARTICLE INSPECTION ### Page 17 ANNEX B S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 17 of 19 1 MAGNETIC PARTICLE INSPECTION OPERATIONS 1.1 In accordance with the instructions given in MM Paragraph 32-11-10, remove the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102 1.2 In accordance with the instructions given in CMM 32-11-19, remove the Wheel Axle P/N M019-01H003-101/-102 from the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. 1.3 In accordance with the instruction given in CMM 32-11-19 and in the Magnetic Testing work instruction given at page 18, perform the magnetic inspection of the LH/RH Wheel Axle P/N M019-01H003-101/-102. 1.4 In case of no findings, proceed to step 1.6. 1.5 In case of findings, discard the damaged LH/RH Wheel Axle P/N M019-01H003-101/-102. 1.6 In accordance with the instructions given in CMM 32-11-19, reassemble the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. NOTE Step 1.7 is applicable only if the wheel is not going to be reinstalled on the MLG strut. assy just after the execution of the magnetic inspection, in order to avoid the possibility of leaving the MLG strut. Assy exposed to possible sources of corrosion. 1.7 Apply corrosion preventive compound MIL-PRF-1617 3 Grade 1 (Tectyl 891D) or Grade 4 (Tectyl 846) on the exposed surface of the threaded end and on inner surface of the end lightening hole of the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. NOTE Step 1.8 is applicable only if step 1.7 has been applied and must be applied at wheel installation on MLG strut. 1.8 Remove the corrosion preventive compound MIL-PRF -16173 Grade 1 (Tectyl 891D) or Grade 4 (Tectyl 846) on the exposed surface of the threaded end and on inner surface of the end lightening hole of the LH/RH enhanced MLG strut. assy P/N 109-0503-45-101/-102. ### Page 18 ANNEX B S.B. N°109EP-168 ALERT DATE: June 28, 2019 Page 18 of 19 REVISION: / 2 MAGNETIC TESTING WORK INSTRUCTION Magnetic Testing and process controls shall be performed in accordance with ASTM E1444 with the purpose to detect any crack in the inspection area, limited to the external rolled thread. Clean the surface with an alkaline steel degreaser (e.g. Ardrox 6333 or Oakite 90) and verify the residual magnetism is less than 3 Gauss. After cleaning, using a magnetic test bench unit equipped with three phase Full Wave DC (3ph-FWDC), perform the magnetic inspection as follows: 2.1 PHASE NO.1: Direct Circular Magnetization Direct magnetization placing the part between heads, as per Figure 1, with 350A, three shots, 0.5s-1.0s each, looking for relevant indications placed longitudinally along the part. Residual Magnetization Method may be used to help in the assessment of the rolled thread area. Acceptance criteria: no cracks are allowed on the part. Figure 1 - Circular Magnetization Note: in this phase, current flows into the part so the use of undamaged soft copper pads is mandatory to avoid arcing or burning on the part. After Phase no.1, perform visual inspection of the contact surfaces to prove no arches or burns are on the part. In case of findings, isolate the part and inform Leonardo Helicopters. 2.2 PHASE NO.2: Longitudinal Magnetization - Induced current magnetization Induced current magnetization by Coil (5 turns), as per Figure 2, with 840A, three shots, 0.5s-1.0s each, placing the area of inspection to the side of the coil looking ### Page 19 ANNEX B S.B. N°109EP-168 ALERT DATE: June 28, 2019 REVISION: / Page 19 of 19 for relevant indications placed transversally to the part, paying particular attention to the inner surface of the thread. Residual Magnetization Method may be used to help in the assessment of the rolled thread area. Acceptance criteria: no cracks are allowed on the part. Figure 2 - Longitudinal Magnetization 2.3 PHASE NO.3: Post-examination demagnetization Demagnetize the part to achieve a residual magnetism less than 3 Gauss, clean the inspection areas with suitable alkaline steel degreaser (e.g. Ardrox 6333 or Oakite 90) and protect them using a thin film of protective oil. ### Page 20 Remarks: Information: SERVICE BULLETIN COMPLIANCE FORM Date: Number: Revision: Please send to the following address: Telephone: Fax: B.T. Compliance Date: Customer Name and Address: Helicopter Model S/N Total Number Total Hours T.S.O. LEONARDO S.p.A. CUSTOMER SUPPORT & SERVICES - ITALY PRODUCT SUPPORT ENGINEERING & LICENSES DEPT. Via Giovanni Agusta, 520 21017 Cascina Costa di Samarate (VA) - ITALY Tel.: +39 0331 225036 Fax: +39 0331 225988 We request your cooperation in filling this form, in order to keep out statistical data relevant to aircraft configuration up-to-date. The form should be filled in all its parts and sent to the above address or you can communicate the application also via Technical Bulletin Application Communication Section placed in Leonardo AW Customer Portal - MyCommunications Area. We thank you beforehand for the information given. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.